As portable electronic devices become more compact, and the number of functions performed by a given device increase, it has become a significant challenge to design a user interface that allows users to easily interact with a multifunction device. This challenge is particular significant for handheld portable devices, which have much smaller screens than desktop or laptop computers. This situation is unfortunate because the user interface is the gateway through which users receive not only content but also responses to user actions or behaviors, including user attempts to access a device's features, tools, and functions. Some portable communication devices (e.g., mobile telephones, sometimes called mobile phones, cell phones, cellular telephones, and the like) have resorted to adding more pushbuttons, increasing the density of push buttons, overloading the functions of pushbuttons, or using complex menu systems to allow a user to access, store and manipulate data. These conventional user interfaces often result in complicated key sequences and menu hierarchies that must be memorized by the user.
Many conventional user interfaces, such as those that include physical pushbuttons, are also inflexible. This is unfortunate because it may prevent a user interface from being configured and/or adapted by either an application running on the portable device or by users. When coupled with the time consuming requirement to memorize multiple key sequences and menu hierarchies, and the difficulty in activating a desired pushbutton, such inflexibility is frustrating to most users.
Some portable electronic devices have displays with information that may be viewed in either a portrait orientation or a landscape orientation. But the input from a user required to initiate a screen rotation between the portrait and landscape orientations may not be readily apparent to the user.
Some portable devices use one or more accelerometers to automatically adjust the orientation of the information on the screen. In these devices, information is displayed on the display in a portrait view or a landscape view based on an analysis of data received from the one or more accelerometers. For these devices, the user may occasionally want to override the orientation displayed based on the accelerometer data. Here too, the user input required to initiate a change between the portrait and landscape orientations may not be readily apparent to the user.
Accordingly, there is a need for portable multifunction devices with more transparent and intuitive user interfaces for implementing screen rotations. Such interfaces increase the effectiveness, efficiency and user satisfaction with portable multifunction devices.